Various and sundry types of prime movers, such as dynamoelectric machines or electric movers, have been operated in particular environments in which foreign ferrous material objects or particles were present. For instance, in the environment of an electric dishwasher, the lower one of the end plates of the electric motor utilized to drive such dishwasher may be located closely to the floor on which the dishwasher is supported, and various foreign ferrous material objects, such as thumbtacks, pins, needles or various other ferrous metal objects or particles for instance, may be inadvertantly disposed on the floor in close association with such one or lower end plate of the electric motor. In the event that the aforementioned lower end plate of the electric motor is formed from a non-ferrous material, it is believed that one of the disadvantageous or undesirable features of such past electrical motors was that the leakage flux emanating from the magnetic field generated by such electric motor upon its energization may deleteriously effect the magnetic ingestion of the foreign ferrous material objects into such electric motor through ambient air passages in the non-ferrous end plate. Thus, an analogous disadvantageous or undesirable feature is believed to be that the magnetically ingested foreign ferrous material objects may have effected short circuiting of the winding means of the electric motor or may have interferred between other associated parts of the electric motor so as to cause a malfunction thereof.
In some other larger prime movers, such as generators or altinators for instance, the winding means also establish a magnetic field upon excitation, and means is associated with the winding for, in effect, trapping or obviating the emanation of leakage flux from the magnetic field which would, of course, establish deleterious heating eddy currents in the prime mover.